What causes pH increase?

[johnlarson66]

I think when you put the drift wood in, you will notice that your pH will drop a little bit below your tap water.

 

[CC917]

If you keep adding "tap water" for evaporated water, the Ph will keep increasing, as when water evaporates, only "water" is lost. Minerals stay in the tank. So, when you using tap water for top-off water, you are just adding more minerals to your tank.

I learned this after I found ph from my tank increased so much. I serached all the information I could find and realized how this happened. Therefore, for small amount of evaporated water, please use pure water instead. I personally use RO water. This will solve the problem.

 

[nynikki]

While on vacation, did you have any casualties? Wouldn't a corpse increase the PH?

 

[fgump]

Wow, this is over a month old. Hmm, to answer some of the questions asked.

what is the pH of the water straight from the tap?

what type of filtration is on the tank? filters that oxygenate the water like air-driven UGFs and HOB filters drive out CO2, which makes the pH of the water drop.

pH of the tap is 7.8, and the tank is normally 7.8. It's a HOB filter (penguin 150 to be exact) .

you aught to check the hardness of your water.. extremely soft water will sometimes change ph quickly.

how were the fish taken care of while you were away? did you have vacation feeders? automatic feeders? a friend come check on them? or did they just tough it out for the week?

The GH is around 12 ppm, with KH around 10-11 ppm. And I was using an automatic feeder. It is a cheap one, and only holds flakes. So my cories would have had to eat any left over flakes that made it to the bottom - they normally get shrimp pellets.

If you keep adding "tap water" for evaporated water, the Ph will keep increasing...

I might add about 1 quart at the most a week if the water gets to low before my weekly water change. But that's always taken care of within a couple of days with my weekly water change. So there's really no chance of build up. And this all happened within a week while I was on vacation.

While on vacation, did you have any casualties? Wouldn't a corpse increase the PH?

No casualties were involved.


And for an update. Once I did my water change, the pH went back to 7.8. And I haven't seen it change since.